Post-stroke depression linked to functional brain impairment

June 5, 2012

Researchers studying stroke patients have found a strong association between impairments in a network of the brain involved in emotional regulation and the severity of post-stroke depression. Results of the study are published online in the journal Radiology.

"A third of surviving a stroke experience post-stroke depression (PSD)," said lead researcher Igor Sibon, M.D., Ph.D., professor of neurology at the University of Bordeaux in Bordeaux, France. "However, studies have failed to identify a link between lesions in the caused by ischemia during a stroke and subsequent depression."

Instead of looking for dysfunction in a specific area of the brain following a stroke, Dr. Sibon's study was designed to assess a group of brain structures organized in a functional network called the default-mode network (DMN). Modifications of connectivity in the DMN, which is associated with internally generated thought processes, has been observed in depressive patients.

"The default-mode network is activated when the brain is at rest," Dr. Sibon said. "When the brain is not actively involved in a task, this area of the brain is engaged in internal thoughts involving self-related and processing."

In the study, 24 patients between the ages of 18 and 80 underwent resting-state (fMRI) 10 days after having mild to moderate . An fMRI imaging study measures metabolic changes in specific areas of the brain. Although many fMRI exams are designed to measure while a patient performs a specific task, during a resting-state fMRI exam, patients lie motionless.

The patients, which included 19 men and five women, were also clinically evaluated 10 days and three months post-stroke to determine the presence and severity of depression and . At three months post-stroke, patients were evaluated for depression using the DSM-IV diagnostic classification system.

Using the DSM-IV criteria, 10 patients had minor to moderate depression, and 14 patients had no depression. Results of the fMRI exams revealed an association between modifications of connectivity in the DMN 10 days after stroke and the severity of depression three months post-stroke.

"We found a strong association between early resting-state network modifications and the risk of post-stroke mood disorders," Dr. Sibon said. "These results support the theory that functional brain impairment following a stroke may be more critical than structural lesions."

According to Dr. Sibon, the widespread chemical changes that result from a stroke may lead to the modification of connectivity in brain networks such as the DMN. He said results of his study may contribute to the clinical management of by providing an opportunity to investigate the effects of a variety of treatments on patients whose fMRI results immediately post-stroke indicate impaired connectivity in the DMN.

Explore further: Activity in brain networks related to features of depression

More information: "Subacute Default Mode Network Dysfunction in the Prediction of Post-Stroke Depression Severity," Radiology.

Related Stories

Activity in brain networks related to features of depression

April 3, 2012
Depressed individuals with a tendency to ruminate on negative thoughts, i.e. to repeatedly think about particular negative thoughts or memories, show different patterns of brain network activation compared to healthy individuals, ...

Depression has big impact on stroke, TIA survivors

March 29, 2012
Depression is more prevalent among stroke and transient ischemic attack survivors than in the general population, researchers reported in the American Heart Association's journal Stroke.

Brain connectivity disrupted in patients with post-concussive syndrome

July 26, 2011
A new study has found that patients with mild traumatic brain injury (MTBI) exhibit abnormal functional connectivity in the thalamus, a centrally located relay station for transmitting information throughout the brain. The ...

Depression associated with increased risk of stroke and stroke-related death

September 20, 2011
An analysis of nearly 30 studies including more than 300,000 patients finds that depression is associated with a significantly increased risk of developing stroke and dying from stroke, according to an article in the September ...

Good ruminations or bad ruminations in the depressed brain?

August 22, 2011
All of us, at times, ruminate or brood on a problem in order to make the best possible decision in a complex situation. But sometimes, rumination becomes unproductive or even detrimental to making good life choices. Such ...

Recommended for you

Mechanism explains how seizures may lead to memory loss

October 16, 2017
Although it's been clear that seizures are linked to memory loss and other cognitive deficits in patients with Alzheimer's disease, how this happens has been puzzling. In a study published in the journal Nature Medicine, ...

Study shows people find well-being more so from special places than from mementoes

October 16, 2017
(Medical Xpress)—A team of researchers at the University of Surrey has found that people experience a feeling of well-being when thinking about or visiting a place that holds special meaning to them. They also found that ...

fMRI scans reveal why pain tolerance goes up during female orgasm and shows brain does not turn off

October 13, 2017
(Medical Xpress)—A team of researchers at Rutgers University has determined why women are able to tolerate more pain during the time leading up to and during orgasm. In their paper published in the Journal of Sexual Medicine, ...

Neuroscientists identify genetic changes in microglia in a mouse model of neurodegeneration and Alzheimer's disease

October 13, 2017
Microglia, immune cells that act as the central nervous system's damage sensors, have recently been implicated in Alzheimer's disease.

Restless legs syndrome study identifies 13 new genetic risk variants

October 13, 2017
A new study into the genetics underlying restless legs syndrome has identified 13 previously-unknown genetic risk variants, while helping inform potential new treatment options for the condition.

Blueberries may improve attention in children following double-blind trial

October 13, 2017
Primary school children could show better attention by consuming flavonoid-rich blueberries, following a study conducted by the University of Reading.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.